Thanks everyone for your feedback. Now I don't feel such an urgent need to go out and find that perfect "one" pair. I think I'll start with the Sugoi Lucky Knickers which will be on sale beginning tomorrow. They slightly flare out below the knee (unlike some knickers). They have the S.100 chamois in them, and it's hard to figure out on the Sugoi website what level of "quality" that is. It is a different chamois from the RS shorts.
I'm going "trying" tomorrow, so I'll let you know how it turns out.